In general, biological tissues have a better functional performance than equivalent synthetic devices when used as a body implant. Tissue grafts are presently largely limited to autologus and allograft tissues that have inherent supply constraints and logistic concerns of harvest, transportation and serologies. Accordingly, there is a need for additional sources of biological tissue grafts. Animal tissues represent such a source. Animal tissues can be relatively easily obtained from slaughterhouses in large quantities. Prior to use, however, these tissues must be treated to remove antigenic proteins that elicit a rejection response by the host following implantation.
Removal of antigenic proteins can be achieved by processing the donor tissue in a manner such that the cellular component of the donor tissue is removed. Many antigenic proteins are present on cellular membranes. Therefore, removal of cells also removes these proteins. After decellularization, the tissue can be packaged and sterilized for use as a biological graft. Grafts can be implanted into humans and other animals to repair, augment or replace natural structures, systems or existing prosthetic devices. These include but are not limited to, cardiovascular, vascular, urogenital, neurological, gastrointestinal and orthopedic systems. Grafts can also be used to provide hemodialysis access.
The present invention provides a method of processing animal tissue so as to render it suitable for implantation into a human (or non-human) host. The invention also provides a method for processing human tissue for use as an allograft implant.